A sweeping analysis of public water systems found that Americans in all 50 states are exposed to drinking water contaminated with multiple harmful chemicals — some above federal legal limits.
Jasmine Laws reports for Newsweek.
In short:
- The Environmental Working Group analyzed 50,000 water systems between 2021 and 2023 and found 324 contaminants, with 12 appearing in all 50 states. Arsenic, barium, radium, and fluoride exceeded U.S. Environmental Protection Agency limits in many communities.
- Nearly half a million Americans were exposed to unsafe levels of arsenic, which is linked to cancer, cardiovascular disease, and developmental harm. Rural and low-income communities face the greatest risk due to limited regulatory oversight and older infrastructure.
- Some chemicals, like trihalomethanes and haloacetic acids — byproducts of water disinfection — are widespread and linked to cancer, yet remain legally allowable at current EPA thresholds. Scientists say these standards may be outdated.
Key quote:
"We do not do a good job of protecting our source waters in the U.S. We have allowed industries to dispose of waste in the environment that has permanently contaminated drinking water sources."
— Natalie Exum, professor at Johns Hopkins Bloomberg School of Public Health
Why this matters:
Drinking water in the United States is under pressure from aging infrastructure, industrial pollution, and chemical residues. While utilities must comply with the Safe Drinking Water Act, federal contaminant limits are not always aligned with the latest science on health risks, especially for vulnerable populations like pregnant women and children. Small or rural systems, often serving low-income communities, struggle most to stay compliant and are least likely to be tested thoroughly. These disparities raise environmental justice concerns, as access to safe water should not be dependent on where a person lives.
Read more: Op-ed: The ghosts in our water
